Method for animal immobilization



Jan. 11, 1966 A. w. HUGHES METHOD FOR ANIMAL IMMOBILIZATION 3Sheets-Sheet 1 Original Filed Sept. 14, 1959 INVENTOR. HAM/1v M Hus/IE5AM M 4 Arfafin'ifl Jan. 11, 1966 A. w. HUGHES 3,228,051

METHOD FOR ANIMAL IMMOBILIZATION Original Filed Sept. 14, 1959 3Sheets-Sheet 2 INVENTOR. 94 um Ml Huewss QYIQLZAFMM Q Jan. 11, 1966 w.HUGHES METHOD FOR ANIMAL IMMOBILIZATION 5 Sheets-Sheet 5 Original FiledSept. 14, 1959 'INVENTOR. A. w m Hus/15$ BY M21 W Y m A 7TOKNE y;

United States Patent Ofiice 3,228,%i Patented Jan. 11, 1966 2 Claims.(Cl. 1745) The present application is a division of my application207,701, filed July 5, 1962 which in turn is a division of myapplication 839,965, filed September 14, 1959, now patent 3,081,483,issued March 19, 1963.

This invention relates to a method for animal immobilization. Inordinary usage the immobilization will be preliminary to slaughteringbut it may also be done in connection with surgical or medical treatmentby a veterinarian.

The invention contemplates confining an animal and immobilizing it byanesthetization while it is confined. In the preferred organizationsuccessive animals are delivered singly into cages mounted on the outerperiphery of a turntable for indexing movement. Each such cage hasbearing supports upon which the cage may be inverted. Each cage also isprovided with animal-confining means for immediate adjustment of thewidth of the cage to the width of the animal so that the animal will befirmly confined when the cage turns over.

As the turntable indexes, the cage in which the animal is confined isquickly inverted, thus confining the animal on its back. Thisimmediately renders the animal completely helpless. On the turntablethere are immobilizing means for application to the individual animalsin their respective cages during turntable rotation. As disclosed, thereare gas masks at each immobilizing station connected with a source ofdesensitizing gas and applicable by an attendant to the individualanimals inverted in their respective cages. Thus, during successiveindexing movements of the turntable, the animals are being subjected toa desensitizing gas which is supplied to their respective masks byforced circulation. Before the turntable has completed one rotation, theanimals are unconscious. This enables the animal to be bled withoutconvulsing, kicking or squealing.

An important feature of this invention consists in the arrangementwhereby the gas used for desensitization of the animals is constantlybeing recirculated through the masks. The masks have special featuresadapting them for application to various sizes of animals, as well as arecirculating arrangement which practically eliminates loss of gas andmakes the invention very economical in use.

Details of the foregoing structure and incidental apparatus will bedescribed specifically with reference to the attached drawings.

In the drawings:

FIG. 1 is a plan view with certain parts omitted of apparatus embodyingthe invention.

FIG. 2 is a fragmentary side elevational view, with certain partsomitted, taken generally on the line 22 of FIG. 1.

FIG. 3 is an enlarged detail View in plan of a set of animal controlgates and means for the operation thereof.

FIG. 4 is an enlarged detail view in side elevation similar to a portionof FIG. 2 but on a larger scale, portions of the apparatus being brokenaway.

FIG. 5 is a View of one of the invertible cages on the turntable as itappears in end elevation in the plane indicated at 5-5 in FIG. 4.

FIG. 6 is an enlarged detail view of the indexing ratchet of theturntable.

FIG. 7 is an enlarged detail view of the immobilizing mask takengenerally along line 7-7 of FIG. 8.

FIG. 8 is an end elevation of the mask shown in FIG. 7.

FIG. 9 is a fragmentary sectional view of a portion of the invertiblecage and bleeding rack and shackle conveyor as viewed from thestandpoint indicated at 9-9 in FIG. 1.

FIG. 10 is a view of the bleeding rack in cross section on the line 1019of FIG. 9.

FIG. 11 is an enlarged detail view with certain parts omitted of themotorized portion of the loading rack taken along line 1111 of FIG. 1.

FIG. 12 is a view similar to FIG. 11 showing a modified loading rampstructure.

FIG. 13 is a view taken in section on the line 13-13 of FIG. 12.

The animals enter the apparatus from a pen 15 of which a portion of thewall is shown at 16 in FIG. 1. They are advanced subject to the controlof metering apparatus which includes a smaller pen 17 communicating withpen 15 through an o ening at 18 and having a movable partition 19pivoted to sweep across said opening from the full line position of FIG.1 to the dotted line position shown therein subject to the control of aram 26.

As the partition 19 approaches the wall 21 of the metering pen 17, theanimal is confined and can progress only forwardiy through the pivotedgate 22. This gate is normally retracted in the position which is shownin full lines and may be advanced by ram 23 to a dotted line positionbehind the animal to prevent him from backing away from the ramp leadingto the immobilizing cages on the conveyor hereinafter to be described.

The ramp includes a relatively fixed ramp portion 24 and a motorizedramp portion 25, the later being in the nature of a treadmill butoperated to advance the animals forwardly. An animal can standmotionless upon ramp portion 24 pending disposition of an animal whichis already being propelled upwardly on ramp portion 25. Between thesetwo ramp portions, there are gates 27, 28 which are oscillatory uponrock shafts 29 and 30, and connected for concurrent operation. In theparticular arrangement shown, gear segments 31 and 32 on rock shafts 29and provide the desired connection. Operation of the illustrated deviceis by means of a ram 33 acting on one of the rock shafts through arocker arm 34. Gates 27 and 28 present arcuate surfaces of substantialuniform radius to the animal which may be standing on the stationaryramp portion 24 so that the opening of the gate does not frighten theanimal or tend to push it rearwardly on such ramp portion.

When the motorized ramp portion 25 is free, the gates 27 and 28 will beopened by swinging them out in front of the animal and the animal willbe caused by prods or otherwise to advance onto the movable ramp portion25 which comprises a conveyor which may be driven from motor 35 (FIG.11) through a gear reducer 36. The animal is laterally confined by sidewalls 37 and 38 which are desirably hinged at their bottom margins asshown at 39 and 40 in FIG. 11, whereby they may be adjusted to confineclosely animals of dififerent sizes, regardless of the animals width.FIGS. 12 and 13 show a motorized ramp portion which is identical so faras the conveyor apron 25 is concerned but has, in conjunction with themotorized supporting belt, side Walls 371 and 381 which likewisecomprise motorized aprons so that the animal will be positivelypropelled forwardly both by the belt 25 on which his feet are supportedand by the sides 371 and 381 which may engage his flanks.

At the forward end of the motorized ramp section 25, there is a loadingstation 125 which desirably includes another set of the pivoted gates271, 281 identical with gates 27, 28 as already described. These areopened as the animal is advanced by the motorized ramp 25 and closedafter .the animal passes through them and enters the cage genericallydesignated by reference character 50.

As shown, there are eight of the cages 50 mounted on a turntable 51. Theturntable may conveniently be supported by wheels 52 from a track 53 asshown in FIGS. 2, 4 and 5.

Each cage comprises a top member 54 and a channelshaped bottom member 55mounted within a ring 56 which supports the weight of the cage uponrollers 57 on the turntable. By rotating the cage upon the bearingsprovided by the ring 56 and rollers 57, each cage individually may beinverted. To steady the cage in its inventing rotation, there is a stud59 on the cage front wall 58 which projects into a bearing 60 mounted onstand 61 on the turntable. With the cage right-side-up .the frontopening which is then above the stud 59 is closed by a hinged frame wallportion 560 which may later be opened in the inverted position of thecage to permit ready access to the animals head and to aid in permittingthe animal to be immobilized.

The cage sides include relatively movable side wall portions 62 (FIG.these being hinged at 63 to the flanges of the bottom channel 55. Thechannel is wide enough for the animals feet. The sides diverge upwardlyat an included angle which may be varied by oscillating the respectiveside walls 62 upon their hinges 63 through the medium of rams 67. Thesides will ordinarily be retracted sufficiently so that the animal willmove freely into the cage. When the animal is in the cage and the gates271, 281 are closed behind him, the rams 67 will be charged with fluidpressure to pivot the side walls 62 of the cage into engagement with.the sides of the animal, thereby closely confining the animal againstmovement in any direction.

The cage is readily rotatable by hand when unloaded. When it contains ananimal, it is, of course, fairly heavy. To assist in the inversion ofthe cage and the animal contained therein, a stationary rubber-coveredrail is desirably provided at 69 in a position to be engaged by the cagering 56 as soon as each cage 50 leaves the loading station in which itregisters with the poweroperated ram 25 and the gates 271, 281. Thus, asthe turntable is indexed, the initial movement will engage the cage ring56 with rail 69 and the rotation of the ring on the rail will invert thecage and the animal. The cages shown at 500 and 501 and all of the othercages (except at the loading station) are shown in their invertedpositions.

Turntable indexing movement may be accomplished in any desired mannerbut it is convenient to use a ratchet 70 mounted on the turntable shaft71 and actuated by a pawl 72 carried by lever 73 which is pivoted onshaft 71 and driven by ram 74 under the control of the operator (seeFIGS. 2, 4 and 6).

As soon as possible after the animal is confined in the cage byengagement between the hing-ed sides 62 thereof (certainly as soon asthe indexing movement of the cage on turntable 51 has progressed to thepoint where the animal is helpless) the animal will be immobilized byapplying over the animals mouth and nose a mask such as that shown at 75in FIGS. 7 and 8. This mask comprises a shell 86 having a gas inlet pipe77 which serves as a handle for the manipulation of the mask. The maskdesirably has a gas circulating return pipe 78. At the front of theshell 76, a slit diaphragm 80 is fixed by a ring 81. The diaphragm has atransverse slit at 82 with beaded margins 83 toward which the diaphragmconverges inwardly at 84 as best shown in FIG.

7. When the mask is forced partially onto the snout of an animal asshown in dotted lines in FIG. 7, the slit receives the animals snout,the beaded margins being separated as shown in dotted lines, the fitaround the animals snout is sufficiently close to require the animal tobreathe air saturated with the immobilizing gas to any desired extent.

To keep the mask from falling away from the animals snout, its gas inlet77 desirably has the form of a rigid pipe serving as a handle formanipulation of the mask and flanged at 86, 87, 88 for engagement withthe forked upper end of a standard 89 as shown in FIG. 1 and FIG. 4. Theselective positioning of the pipe 77 with the respect to the standardwill hold the mask to the animals head in any position at which therespective flange 86, 87 or 88 is engaged with the standard 89. Aflexible hose 90 connects the end of pipe 77 with a manifold 91 thatencircles the gas mixture tank 92.

The gas cylinder 93 opens into the tank 92 through an equalizer valve 94which maintains the mixture approximately constant but which forms nopart of the present invention. A blower 95 delivers the mixture from thetank 92 into the manifold 91 which supplies the various masks. Theflexible return hoses 78 from the several masks lead into a manifold 96whereby the mixture is recirculated into the tank 92. The slightpressure provided by the blower 95 assures that any leakage through thediaphragm which confines the animals head will tend to be outward ratherthan inward. At the same time, there is not a great deal of pressurewithin the mask because of the recirculation provided by the hoses 78which return the gas to the tank at the suction side of the blower. Themask eliminates the tunnel and pit methods in present day use, makingpossible a more efficient use of gas and rendering animals unconsciousin a shorter time. The animals are so firmly confined, they are unableto thresh wildly about (as with tunnel and pit methods for effectingimmobilization) thus preventing them from causing extensive carcassdamage to themselves. The mask is of considerable importance forconfining gas if lighter than air immobilizing gases are used.

If the animal is merely to be slaughtered it is not necessary to use agas which anesthetizes the nerve centers of the animal. In preferredpractice, the gas used is carbon dioxide. Nitrogen, argon or othernon-toxic inert gases which temporarily render the animal unconscioussimply by depriving him of adequate oxygen, could also be used.

The weight of the animal in the inverted cage will tend to maintain thecage inverted. When the animal is withdrawn, following immobilization,the cage will tend to return by gravity to its original erect position.

The immobilized animals may, for some purposes, be unloaded at anystation in the course of advance of their respective cages with theturntable. In preferred practice of the invention, the unloading station100 is immediately adjacent the loading station 125. The unloadingstation is that at which FIG. 1 shows a cage 506. Extending outwardlyfrom the unloading station is the bleeding rack 100 as best shown inFIGS. 1, 9, 10. This rack comprises a frame 101 with a supporting strip102 on which the weight of the immobilized animal is carried. Atsuitable spacing along the sides are tubular bars 103, 104, 105 betweenwhich the body of the animal is confined. Beneath the rack is ablood-collecting trough 106 which is preferably inclined or has apitched bottom 107.

Extending longitudinally along the rack overhead is a shackle conveyorrun 110. Only a portion of the endles-s conveyor is illustrated. Inpassing over a sprocket 111 remote from the turntable, the conveyor hasa run extending upwardly as shown at 112 in FIG. 9.

Depending at intervals from the conveyor are the thongs 113 withshackles 115 at their ends. An attendant will engage such a shackle withthe hoof of an immobilized animal as the latter lies within the cage atthe unloading point. The side wall portions 62 of the cage beingretracted by the relief of pressure in the ram cylinders 67, the animalwill be released so that the continued movement of the conveyor willcause the shackle to pull the animal along the rack. Immediately theanimal will be stuck by opening a blood vessel in its neck.

As the animal slides along the rack, its blood will flow into the trough106 and will be delivered to a suitable point of collection. Meantime,by the time the conveyor run 112 lifts the shackle and the animal towhich it is attached, the animal will no longer have strength to resistand will no longer have suflicient blood left in its veins to causedamage to the meat if a blood vessel ruptures in the animals shackledleg when the animal is lifted. Thus, damage to or los of the valuableham meat is almost completely eliminated. See my Patent 2,978,737,whereby the use of such a bleeding rack and the method of immobilizingand bleeding as above described has been disclosed. An important featureis to carry the weight of the animal along the bleeding rack untilbleeding has progressed sufiiciently far so that no damage to theshackled leg will result when the animal is lifted. The entire animalweight is supported from below, with or without movement along the rack,until the bleeding is almost completed, rendering it incapable ofeffective resistance, after which the animal is then lifted andsuspended from above for the completion of bleeding.

Apart from the subcombination claims relating to bleeding, the inventionincludes a method of immobilization which involves the lateralconfinement of an individual animal while the animal is in the course ofmovement on the turntable conveyor along a predetermined path of travelbetween the loading station 125 and the discharge station 100. FIG. 5shows the animal so confined. The method contemplates the animalsinversion immediately preceding the immobilization. As explained above,the inverted animal is completely helpless and cannot resist the ensuingimmobilization by gas or otherwise. The method includes the applicationof a mask to each individual animal, a supply of the immobilizing gas tothe mask preferably being recirculated therethrough. FIG. 7 illustratesapplication of the gas mask over the snout of the animal whereby hisenose is completely enclosed. Thi eliminates the tunnel and pittreatments heretofore proposed and makes much more efiicient use of thegas. A single operator stationed on the turntable can do theimmobilizing by applying the gas mask when the animal is fixed againstmovement and removing it when the animal has been immobilized by thegas. When the cage stops in registry with the unloading station 100, ashackle connected with the overhead conveyor will be attached to thehoof of the immobilized animal as above described. The lateral pressureof the movable side walls of the cage will be relieved and the conveyorwill draw the animal from the cage and along the bleeding rack.

The only interruption in the entire procedure is that required forloading the animal into the cage and confining it immovable therein.

While the invention has been described with particular reference toanimal slaughtering, those skilled in the art will recognize thatanimals may be handled in the appropriate portion of this apparatus forother purposes, including treatment by a veterinarian, the lateralconfinement of the animal and inversion of his cage being sufficient,without more, to protect both the animal and the veterinarian.Similarly, for other purposes, it may be desired to administer gas to ananimal with-out the inversion step and for purposes other thanslaughtering. The mask, particularly as used with the means forpreventing displacement thereof by locking the mask and animal againstseparation, is a convenient device for these purposes.

I claim:

1. A method of immobilizing animals which consists in the steps ofconfining an animal, applying a gas mask over the mouth and nostrils ofan animal so confined, supporting the mask against withdrawal from themouth and nostrils of the animal, and substantially continuouslyrecirculating an immobilizing gas between the mask and a source of suchgas until the animal is immobilized.

2. A method according to claim 1 in which the step of confining theanimal further includes inverting the animal.

References Cited by the Examiner UNITED STATES PATENTS 11/1960 Wiese128-188 1/1964 Hughes 17-45

1. A METHOD OF IMMOBILIZING ANIMALS WHICH CONSISTS IN THE STEPS OFCONFINING AN ANIMAL, APPLYING A GAS MASK OVER THE MOUTH AND NOSTRILS OFAN ANIMAL SO CONFINED, SUPPORTING THE MASK AGAINST WITHDRWAL FROM THEMOUTH AND NOSTRILS OF THE ANIMALS, AND SUBSTANTIALLY CONTINUOUSLYRECIRCULATING AN IMMOBILIZING GAS BETWEEN THE MASK AND A SOURCE OF SUCHGAS UNTIL THE ANIMAL IS IMMOBILIZED..